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-rw-r--r--arch/x86/kernel/setup_percpu.c34
1 files changed, 4 insertions, 30 deletions
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index efbafbbff584..90b8e154bb53 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -77,30 +77,6 @@ static void __init setup_node_to_cpumask_map(void);
77static inline void setup_node_to_cpumask_map(void) { } 77static inline void setup_node_to_cpumask_map(void) { }
78#endif 78#endif
79 79
80/*
81 * Define load_pda_offset() and per-cpu __pda for x86_64.
82 * load_pda_offset() is responsible for loading the offset of pda into
83 * %gs.
84 *
85 * On SMP, pda offset also duals as percpu base address and thus it
86 * should be at the start of per-cpu area. To achieve this, it's
87 * preallocated in vmlinux_64.lds.S directly instead of using
88 * DEFINE_PER_CPU().
89 */
90#ifdef CONFIG_X86_64
91void __cpuinit load_pda_offset(int cpu)
92{
93 /* Memory clobbers used to order pda/percpu accesses */
94 mb();
95 wrmsrl(MSR_GS_BASE, cpu_pda(cpu));
96 mb();
97}
98#ifndef CONFIG_SMP
99DEFINE_PER_CPU(struct x8664_pda, __pda);
100#endif
101EXPORT_PER_CPU_SYMBOL(__pda);
102#endif /* CONFIG_SMP && CONFIG_X86_64 */
103
104#ifdef CONFIG_X86_64 80#ifdef CONFIG_X86_64
105 81
106/* correctly size the local cpu masks */ 82/* correctly size the local cpu masks */
@@ -207,15 +183,13 @@ void __init setup_per_cpu_areas(void)
207 per_cpu(cpu_number, cpu) = cpu; 183 per_cpu(cpu_number, cpu) = cpu;
208#ifdef CONFIG_X86_64 184#ifdef CONFIG_X86_64
209 per_cpu(irq_stack_ptr, cpu) = 185 per_cpu(irq_stack_ptr, cpu) =
210 (char *)per_cpu(irq_stack, cpu) + IRQ_STACK_SIZE - 64; 186 per_cpu(irq_stack_union.irq_stack, cpu) + IRQ_STACK_SIZE - 64;
211 /* 187 /*
212 * CPU0 modified pda in the init data area, reload pda 188 * Up to this point, CPU0 has been using .data.init
213 * offset for CPU0 and clear the area for others. 189 * area. Reload %gs offset for CPU0.
214 */ 190 */
215 if (cpu == 0) 191 if (cpu == 0)
216 load_pda_offset(0); 192 load_gs_base(cpu);
217 else
218 memset(cpu_pda(cpu), 0, sizeof(*cpu_pda(cpu)));
219#endif 193#endif
220 194
221 DBG("PERCPU: cpu %4d %p\n", cpu, ptr); 195 DBG("PERCPU: cpu %4d %p\n", cpu, ptr);